chemical process inustries

8/9/2019 Chemical Process Inustries

1/106

VEL TECH VEL TECH MULTI TECH VEL TECH HIGH TECH

UNIT I

TWO MARKS

1. Define ISA?

A standard atmosphere is defined in order to relate flight tests, wind tunnel

results, and general airplane design and performance to a common reference. The

standard atmosphere gives mean values of pressure, temperature, density and

other properties as functions of altitude: these values are obtained fromexperimental balloon and sounding rocket measurements combined with a

mathematical model of the atmosphere.

2. Define Aerodynamic lift, drag and moments?

Consider the body sketched in figure oriented at any angle of attack to the

free-steam direction. The free steam velocity is denoted by V and is frequently

called the relative wind. The resultant aerodynamic force R, is inclined rearwardfrom the vertical, as shown in figure. (Note that, in general R is not perpendicular

to the chord line. By definition, the component of R perpendicular to the free-

stream velocity is the lift L, and the component of R parallel to the free steam

direction is the drag, D.

Figure: Lift , drag and resultant aerodynamic force


1


2/106


Figure: (a) Moment about the quarter-chard point, (b) Moment about the

leading edge.

3. Define centre of pressure?

The centroid of the distributed load on the body is the point through which

the equivalent concentrated force acts. This point is called the center of pressure.

4. Define Aerodynamic co-efficients?

The lift, drag, and moment coefficients for a given body, denoted by C L , C D

and C M, respectively , as follows:

D

...(1)

C ...(2)

L

LC

q S

D

q S

=

=

...(3)M

MC

q Sc

=

Where q is the dynamic pressure, defined as

21 ....(4)2

q V

=

And c is a characteristics length of a body (for an airfoil, the usual choice for

c is the chord length). Let us define the following similarity parameters:


2


3/106


Re number (based on chord length): = ..(2.5)

Mach number , M

V Cynolds

V

a

=

5. Define Stalling ?

Figure: Sketch of generic lift curve.

At high angles of attack, the lift coefficient becomes non-linear, reaches a

maximum value denoted by (c 1 ) max in figure, and then drops as is further

increased. The reason for this drop in c 1 at high is that flow separation occurs

over the top surface of the airfoil and the lift decreases (sometimes precipitously).

In this condition, the airfoil is said to be stalled.

6. Define Aspect ratio and taper ratio?

An important geometric property of a finite wing is the aspect ratio AR,

defined as AR b 2 /S.


3


4/106


Figure: Aspect ration2

1

r

C rat!o =

C

bAR Taper

S=

7. Define pressure drag and friction drag?

Pressure drag- due to a net imbalance of surface pressure acting in the drag

direction

Friction drag due to the net effect of shear stress acting in the drag

direction.

8. What is mean by drag polar?

For every aerodynamic , there is a relation between C D and C L that can be

expressed as an equation or plotted on a graph. Both the equation and the graph

are called drag polar.

PART =B

9. Derive the relationship between the pressure and density variation in the

isothermal regions and gradient regions of the standard atmosphere?

The keystone of the standard atmosphere is a defined variation of T with

altitude, based on experimental evidence. This variation is shown in figure.


4


5/106


Note that it consist of a series of straight lines, some vertical (called the

constan d temperature, or isothermal, regions) and other inclined (called the

gradient regions) given T = T(h) as defined by Figure, Then , = (h) and =

(h) follow from the laws of physics, as shown below.

First, consider again CHEMICAL ENGINEERING

CHEMICAL PROCESS INDUSTRIES II


5

"ressurealt!tude = #$$$ m = # %m&em'erature alt!tude = 5$$$ m = 5 %m


6/106


UNITI

PARTA

1. What is meant by Pulping?

Paper production requires a disintegration of the bulky fibroins material to individual (or)

small agglomerate fibers. This is called pulping.

2. What are the raw materials used in paper Industry?

(i) Softwoods

(ii) Grasses and

(iii) Straws

(iv) Cotton linters

(v) Hardwoods

3. What is meant by Pulp?

Pulp is a commercial cellulose from bamboo, bagarre wood, etc by mechanical (or) chemical

methods.

4. What are the methods used in the manufacture of industrial pulp?

i) Sulfate (kraft) process

ii) Sulfite process

5. Write the reaction for the sulfate process?

(

2

tan

R CooNa

RoHR R NaoH

R R Na S meccap s

+

+

6. Briefly explain about soda process?

Small tonnage (25-50 tons/day) plants initially set up in India use a process which involves

hydrolysis with NaoH and Na2co3in 4:1 ratio Advantage is lowest cost of chemicals are notrecovered and sulfur requirement. The soda process produces inferior grade pulp at high cost in


6


7/106


batch operations and is not used for modern, large tonnage pulp plants.

7. What is called as Paper?

It is defined as the felted sheets of fibrons, usually cellulose and generally formed on a fine

wire screen from a water suspension

8. What are the steps involved for the manufacturing of paper?

i) Preparation of filter suspensions.

ii) Forming a wet webiii) Pressing the wet web

iv) Drying the sheet

9. For what reason the filters are added for the paper manufacturing?

They are added to improve the brightness, bulk, flexibility, capacity, softness and weight of

the finished paper.

10. What is the reason for doing sizing?

Sizing is an important ingredient often added to the slurry to reduce water (or) other liquid

penetration into certain paper products

11. What are the coloring agents added in the paper manufacturing process?

Coloring agents are mixed in to the slurry before processing. These are generally synthetic

organic dyestuffs; but some colouring is done by water- insoluble pigments.

12. Describe the Digestion process involved in the pulp production?

Hogs with bark are debarked by tumbling and rubbing action, then conveyed to chipper

where large rotary disks with many have knives reduce the wood to 2-5 cm flat chips.

The chips are recharged thro a rotating tapered plug in to the lift line where circulation

digestion liquor at 12 atms.

13. What is termed as Bleaching of pulp?


7


8/106


Removal of colour residue (or bleaching may be accomplished by use of one of various

oxiding agents which must be cheap and have a minimum degrading action (or) cellulose.

14. What is the use of lignim obtained in paper industry?

It is used as fuel used itself in pulp and paper production Industry.

15. Explain the term paper?

Paper is defined as matted (or) felted sheets of fibers, usually cellulosic and generated

formed on a fine wire screen from a water suspension.

16. Explain the procedure for the formation of fiber suspension?

Pulps are water slurried to - % fiber content by mechanical disintegrators of various

designs . Then we are adding filters, sizing, coloring agents to improve the strength.

17. Define Inversion of sugar?

In handling sucrose, particularly in the sugarcane before pressing, the inversion to

monosaccharide is possible.

12 22 11 2 # 12 # 1# 12 #cosSucrose d glu e d fructose

C H O H C H O C H O

+ +

18. What are the by-products of sugar manufacture?

i) Molasses

ii) Bagasse

iii) Press mud

19. What is the use of Bagasse?

It is the by-product used in sugar industry used as fuel in boilers for generation of stream

raw material for the paper industry as well as cogeneration of power.

20. What is the use of molasser?

Molasses in an important by product having strong linkager with alcohol industry. 70% ofthe molasses is used for the manufacturer of industrial alcohol and balance 30% for potable


8


9/106


alcohol.

21. Define the term Black strap molasses

The mixture of crystal and syrup is separate via high speed basket centrifugal. The syrup is

concentrated and cooled successively to obtain one (or) two more crops of crystals. The final

mother liquir is known as black strep molasser.

22. Define the term starch.

Starch is a high polymer carbonhydrate occurring in grains and roots in the form of

granules of 3-100 size. These granules can be extracted from the grains by water hydration of he

cells.

23. What are the type of pulp?

i) Sulphate pulp

ii) Sulphite pulp

24. What are the applications of starch?

i) Starch has considerable usage in industry

ii) Hydrolysed products used in food industry

25. What are the recent improvements in the paper making process?

i) Increase in the wet strength of paper products

ii) Modification in paper machine to improve properties of paper

26. What are the type of starches?

i) Dextrin

ii) Dialdehyde starch

iii) Starch phosphate

27. What is viscon rayon?

It is a thread like structure of varying lengths capable of being woven of spume into larger


9


10/106


units.

28. What are the miscellaneous starch derivates?

i) Rice starch

ii) Amylose

iii) Potato starch

29. What are the application of the starchus?

i) Starch has considerable usage in industries

ii) Hydrolyzed products used n food industries

30. What is amylase and amylopectin?

Amylose occurs to the extent of 27% in corn starch and 73% is amylopectinAmylose is a linear chain of dextore

Amylopectin is almost amylore and is being grown in increasing amounts.

31. What do you know about cane sugar refining?

Quality of sugar will be poor The impurities are coagulated by the addition of vegetable bare to produce good qualitysugar.

32. Which machine is used in sugar manufacturing?

Fourdrinler machine

33. What are the products of the glorifications of coal?

Producer gas Water gas

34. Write the two phases in the reduction of raw wood?

Cellulose


10


11/106


Non cellulose

35. What is the other name for the coal gasification process?

Kopper tozex process

36. What are the sizing agents?

Rosin Wax emulsions

37. What are the types of paper products?

Wrapping papers Tissue paper Book paper Paper board

38. Give examples of fiber types cellulose?

Viscose Rayon

39. What are the uses of coal?

Coal gas, ammonia, benzene and phenol in destructive distillation, Aromatics byhydrogenation.

Organic acids under controlled oxidation

40. Give examples of beaching agents?

Sodium bisulphate Chlorine Sodium dithionate

41. What are detergents?

Detergents covers scientifically both soap and synthetic detergents. But, it is widely used to

indicate synthetic cleaning compounds as distinguished from soap. Detergents may react with the

hard water ions, resulting products are either soluble (or) remains colloid ally dispersed in water.


11


12/106


42. What is the use of foundriniers machine?

It is used in the manufacture of

i) paper

ii) sugar

iii) dyes

43. List some name of regents used for the chemical treatment of wood chips.

The different reagents are.

i) Sulphiteii) Sulphate

iii) Causing soda and / or soda ash

44. What is the chemical formula for paper makers alum?

Al2So418H2O

45. What is meant by affination in sugar industry?

In sugar industry the same sugar crystal are treated with a heavy syrup in order to remove

the film of adhering molasses. This refining step is called affination.


12


13/106


PART B

1. Explain the sulphate process for the production of pulp with neat flow sheet?

Logs with bark and debarked by tumbling and rubbing action, then conveyed to chippers

where large rotary disks with many heavy knives reduces the wood to 2-5 cm flat chips.

The chips are metered via star valve to a deareator pre heater. After several minutes, the

chips are discharged thro a rotating tapered plug into the lift line where recalculating digestion

liquor at 12 arms. Transfer chips to the upper soaking zone of the 25-30 m tall digestion to wet.

The digestion chips are cooled at the base of the towel by injection of cold back liquors.

This s to avoid mech. Weakening of fibers from stream explosion of the hot liquor when passed

thro the blow down valve. The pulp liquor slurry is passed thro the value to blow tank where

residual heat is removed in the form of stream which passes overhead with turpentine vapour to

the chip preheater. The pulp is filtered to separate black liquor and screened to remove wood

knots and other undigested residue. The blown pulp goes either to produce finishing operations

(or) the bleaching plant.


13


14/106


Figure: Process Flow Sheet

Preparation of wood pulp from sulphate process

2. Explain the recovery of chemicals flam digestion tower in sulphate process


14


15/106


Figure: Chemical Recovery From Sulphate Process

The equation is

a) Smelting furnace

2NaR (highnium salt) + airNa2Co3+ Co2

Na2So4+ 2c (flam R)Na2s + 2 Co2

b) Caustcizing

Na2CO3(ag) + ca(OH)2(s)2NaOH(ag) + CaCo3(s)

CaCo3Cao + Co2

Cao + H2oCa(OH)2

Process description

Black liquor from the blow tank containing 98.99% of the digestion chemicals which must

be recovered to avoid water and air pollution problems and to provide a balanced economy of

Opn.

Multiple effect evaporation using 5-6 stage of calendar followed by disk evaporates contact


15


16/106


rates the liquor from 15-18%. Solids to the point where combustion can be strained in a smelting

waste heater boiler.

The molten smelt falls into the dissolved where it contacts cold H2o to yield green liquor

solution. The insoluble imparities, such as in carbon are unsettled out and the clear liquor

causticized by adding lime.

3. Explain the main reaction involved in sulphate process and process reactants and Bypro

chemical Reaction:

Digestion Hydrolysis and volatilization of liquor

2

tan

nR COONa

RoHR R NaoH

R R Na S melcap s

+

+

Z

]

Chemical recovery from black liquor:Wood digestion liquor)

a) Smelting Furnace:

2NaR (liquor salt) + airNa2Co3+ Co2

Na2SO4+ 2C (from R)Na2S + 2Co2

b) Causticizing:

Na2Co3(ag) + Ca(OH)2(S)2NaoH (ag) + Caco3(s)

Cao + H2OCa(OH)2

By product utilization:

The germ resin and oil friction from softwood furnishers the naval products of tall oil rosinturpentine.

The use of liquor thus used in low rubber return a fuel within the pulp and paper plant.

4. What is paper? Explain the types of paper and various raw materials?

Paper is defined as matted (or) felted sheets of fibers, usually cellulosic and generally

formed on a fine wire screen from a water suspension.

Types of paper products


16


17/106


Wrapping paper Bay paper, grease proof paper

Tissue paper cigarette, carbon, toilet-towel, napkin paper Writing paper bond weight linear paper

Ground wood printing paper catalog, newsprint, tablet porter, wall papers.

Paper board heavier less flexible, laminated paper stock

Raw Materials:

Fibrous raw material:

Paper pulp

Ground wood, bleached and unbleached sulfite and sulfate, semi- chemical pulp

Reuse pulp:

Paper products such as news papers and paper board and re-pulped and mixed with new

pulp for paper mill feed stock.

Non-fibrous raw material

Inorganic raw materials

Clay, talc, titanium dioxide zinc sulfide, alum, organic raw material

Rosin, glue, casein, waxes, glycol, dyestuffs

5. Explain the manufacturing process for paper.

Steps involving in paper making process:

o Formation of wet web

o Pressing the wet sheet

o Drying the sheet

o Addition of ingredients like filter, sizing agents, colouring agents etc.


17


18/106


Paper making Process:

Figure: Schematic drawing of a paper making process

6. Explain the steps involved in the paper production process.

Preparation of fibre suspensions:

Pulps are water slurried to - % fiber content by mechanical disintegrators of variousdesigns. These usually consists of rotating drums with knife attachments (or) rotating stationary


18


19/106


disks to produce vircous shear. Such operations are called beating and refining.

Filters are added to the slurry to the increase brightness, bulk flexibility, opacity, softnessand weight of finished products.

Sizing is an important ingredient of the added to the slurry to reduce water (or) other

liquor penetration in to certain paper pots.

Colouring agents are also mixed in to the slurry before processing. These are generally

synthetic organic stuffs, but some colouring is done by H2O insoluble pigments.

Formation of wet web:

A wet sheet is formed by running 99 of water fiber flurry evenly onto a moving endless

belt of wire cloth at speeds of 50m/min for fine paper to 500 m/min for newsprint. Water drains

by gravity, a part is next removed by a paper roll and then by suction roll. The screen also a side

wire shaking motion to give better interlocking of fiber on the mat.

Drying the sheet:

The sheet from the press section has sufficient strength to carry it own weight. It is passedthro smoothly rolls, then a series of steam-heated metal cylinder where heat and moisture are

transferred to a felting (or) convering belt.

7. Explain the process with neat flow diagram for the extraction of sugar from sugar cane.

Canes are shredded in crushes and then squeezed thro a series of pressures mills

containing grooved walls.

The juice is treated with CaHPo4, followed by lime to precipitate the colloids So2is nextbubbled thro until the PHis 7.0 to 7.1 . This is for the flocculation of impurities. So2acts as

bleaching agent.

Closed steam in a coil is used to heat and further flocculate the impurities in a continuous

setter.


19


20/106


Figure: Extraction of Sugar from Sugarcane

The clarified liquor overflows to the evaporator. The underflow muds are processed on a

continuous rotary press to recover sugar solution.

The clarified juice is concentrated from 80-85% water 40% in 3 (or) 4 effect evaporator with

crystallization.

The mixture of syrup, called massecute is separated via high speed basket centrifugal. The

syrup is re-concentrated and cooled successively to obtain one (or) 2 crops of crystals. The final

mother liquor is termed as Black strap molasses.

8. Explain the starch production from maize.

Process description:

The major source of starch in maize and a wet milling process for the removal of starch will

be presented.

Maize kelnels containing 60-65% starch are screened and air cleans, then steeped in 50-55C

water containing 0.15 0.30% So2grinding mills to rapture the cells and loosen the oil germ whichis floated off in a large slurry tank.


20


21/106


The starch portion of the kernel is wet ground on burrstone mills and passed over nylon

cloth where water washes the starch thro and leaves the fiber and hulls on the screen.

The starch suspension in the underflow from the screen contains glucton (water in soluble)

which is separated as the light fraction in a 2 stage centrifugal operation.

The starch is recovered as filter cake on continuous rotary filter. It can be dried powdered

and sold as peal starch.

Figure: Starch Production from maize

9. Explain the production of Dextrin by starch hydrolytes in a fluidized bed

( ) ( )# 1$ 5 # 1$ 5 xHeln

C H O eat C H Ox

A batch operation charges 5-10 starch to an air suspended fluidize. Heat is added via

rectangular shaped.


21


22/106


Figure: production of dextrin by starch hydrolysis in a fluidized bed

Plate coils, using 10-12 atms. Steams, in the upper section of the fluidizer. The charges reaches

65- 170C, depending on the degree of hydrolysis desired, within 30min. the charge reaches 65-

170C, depending on the degree of hydrolysis desired. Within in 30 min Hcl vapour is introducedin to the re-circulating air steam and de-polymerization continued for 1- 8 hr.

10. Explain starch derivations.

Description:

An oxidation form of starch which is used in the paper industry as a wet strength additive-

and in adhesives.


22


23/106


Chemical Reactions:

a) Oxidation of Starch

HIO3+ H2O

b) Regeneration

Anode of electrolysis cell:

HIo3+ 2oHHIo4+ H2o

Starch slurry contact periodic acid in a batch reaction with the oxidized starch separated from

iodic acid solution by centrifuging. The reduced solution is re-oxidized as the anolyte in a unique

electrolytic cell.

11. Describe Starch Phosphate

A starch which is water soluble, has excellent freeze thro stability good tricking power

excepted usage is as thickness in canned and brozen foods, addresively , emulsion, paints

formulatons, Pharmaceutial filters and binder.


23


24/106



Starch slurry is a heated with alkaline phosphate solutions at various conditions depending

upon degree of estirification. Control of PH (8.5-9.5), temperature (50-70C) used. The water

soluble solutions are filtered and the filtered spray dried.

12. Describe briefly about the starch structure and properties.

Starch is a high polymer carbohydrate occurring in grains and roots in the form of

granules of 3-100size. These granules can be extracted from the grains by water hydration ofcells.

Chemical Formula : C6H10O5

Chemical structure

Amylose (or) Linear polymer

Amylopectin (or) branched chain polymerization:


24


25/106


Values from 200- 500C, comment industrial starches from maize contain 15-30% amylase and87.70% amylopection

13. Explain the section of coal garifier


25


26/106


Figure: Section of coal gasifer

Coke (or) non coking coal taldistillation relate mainly to competitive petrochemical routs

to such products as aromatics hydrocarbons and phenol.

Raw material:

Coke (or) non-coking coal

Reaction:

4C+O2+ 2H2O 4Co+2H2

14. Explain the process in detail for coking of coal.


26


27/106


The high temp carbonization of coal is carried out at 900C to 1.150C in batteries of tall

vertical ceramic chambers separated by heating flores. Each chamber may be 13ft high, 38 to 40ftlong and tapering in width from 17-18 inches at one end to 15-16 inches at another end. One even

may hold 16-24 tons of coal and a battery may contain 10-100 ovens. Crashed coal is dropped in to

an over preheated to 1,100C.

After a heating tie of about 17 hrs doors on the ends of the over are opened and the entire

red hot coke mars is pushed out into a quenching car by a power driven ram. After draining off

the water the coke is crushed and screening prior to use as fuel. The gar issuing from the over

during the coking process is cooled to remove tars, scrubbed with water to remove NH3

15. Define the hydro formation of coal:

The coal may be fed to hydro formation process is various ways. Each of them requiring

produced coal.

Figure: Process of powdered coal to give aromatic liquids

UNIT II


27


28/106


PART A

1. What are edible oil?

These are the mixture of glyserides of fatty acids.

2. Give any two examples (or) Uses of non-edible fats?

Manufacture of soap

Neam oil is used as pesticide

3. What is necessarily for the hydrogenation of oil?

To remove double bonds raise the melting point of the fat and improve its resistance to

rancid oxidation.

4. What are oils and fats?

Mixtures of glycerides of fatty acids where R1R2and R3are not necessity the same.

R1Coo CH2

R2COO CH

R3CooCH2

Oils are liquids and fat are solids at normal temperature

5. Define WAX:

Mixed enters of polyhydric alcohols other than glycerin usually solids at room temperature.

6. What are surfactants?

Any compound that affects surface tension where dissolved in water (or) water solution (or)

which similarly affects interfacial tension between two liquids.

7. Write soponification reaction?


28


29/106


R.CooH+ M.OHR.Coom +H2O

Glycerides Caustic Soap of Higher Fatty acids

Malkali metal such as Na (or) K

8. Give the fat splitting reaction:

Acid hydrolysis of glycerides followed by alkali addition (Rc000),

c3H5+H2ORcooH+C3H5(OH)

9. What are the uses of fatty acids?

As magnesium striates in face powders

Lithium steerages as a component of greases

Rosin soap consumed as a sizing of paper

10. Types of Surfactants

Quatenary ammonium compounds dialky, dimethy, quaternary ammonium.

Diamido alkoxylated quaternary ammonium compounds Amido imidazdiniumcompounds.

11. What are the advantages of the continuous hydrolysis and saponification process?

(i) Flexibility in control of product distribution

(ii) Higher glycerin yields

(iii) Less off colour production and

(iv) Requires less space and ma-power

12. What are the raw material for the manufacture of soap?

Vegetable oils

Caustic soda

13. What are the products of saponification of a fat?

The products are

Glycerol


29


30/106


Salts of higher fatty acids

14. What is meant by massecuite?

The mixture of crystals and syrup is called massecuite.

15. What are the favorable condition to maintain higher melting point fats of maximum

stability for cooking purpose.

The favorable condition to maintain higher melting points fats of max. Stability for cooking

purposes are higher pressure (2 to 3.5 atm) and lower temperature (20-160c)

16. What is the structural formula for sucrose:

17. Define the term saponification value?

The number of milligrams of potassium hydroxide required to saponify one gram of the oil.

18. Write the uses of Citric acid:

As an acidulant in carbonated beverages, jams, jellies and other food stuffs.

19. Give any fields where soaps and detergents are used?

Textile manufactures Sanitation

Food processing Shaving soaps Paints and emulsion formation etc.

20. Give the usage Enzyme named Zymase in Fermentation Industry?


30


31/106


Zymase is used to convert glucose into ethyl alcohol and carbon-di-oxide.

21. Write the reaction for the production of Nickel catalyst?

2Ai.Ni+6NaoHNi* + 2NaAlo3+3H2

Alloy (Raney Nickel)

22. Names the raw material in the production of a soaps?

(i) Refined Tallow

(ii) Refined grease (iii) Coconut and palm oils

(iv) Metal oxide such as Zno used as catalyst.

23. What are the different chemical reactions involved in the fermentation industries?

(i) Oxidation

(ii) Reduction

(iii) Hydrolysis

(iv) Esterification

24. What are the products of Saponification of fat?

(i) Glycerol

(ii) Salty of higher fatty acids

25. Write the chemical formula for silicic acid?

The chemical formula is H2Sio3

26. What is the use of enzyme glucose iromers?

It is used to produce high fructose syrup from Corn.

27. Write the composition alcohol?

It is alcohol contains 95% of alcohol and 5% water is known as industrial alcohol.

28. What are the major engineering problems involved in fermentation industries?


31


32/106


(i) Kinetics of submerged, aerobic fermentation

(ii) Scale up of submerged fermentation(iii) Air sterilization

(iv) Media sterilization

(v) Continuous virus batch operation.

29. Define Beer:

Separations of 8-10% alcohol in the fermentation liquor is called Beer.

30. Which type of alkali is added to removed free fatty acid in oil-extraction?

In oil extraction, alkali such as Naoh (or) Na2Co2is added to remove free fatty acids.

31. What is the used of Hydrogeneration?

It is used to remove double bonds raise the melting points of the fat, and improve its

resistance to ran acid oxidation.

32. What is the use of sodium silicate?

It is used in detergents to avoid aluminum corrosion in washing machines.

33. Define the term fermentation?

It is defined by microbial process controlled by humans that produces useful products.

34. What are the Unicellular enzymes?

Yeasts

Bacterias

35. What is the main-chemical reaction involved in the manufacture of alcohol and by products

acetic acid and glycerin?

C6H12O6 C2H5OH+2CO2

Monosaccharide alcohol OH =-130 KJ

2C6H12O6+H2O


32


33/106


Monosaccharide C4H5OH+CH3COOH +2CO2+2C3H8O3

Alcohol acetic acid

36. What are the uses of detergents?

(i) A cleaning agent

(ii) A water softener

37. What must be the temperature kept for the manufacture of ethanol?

20-30C

38. What is meant by fusel oil?

Mixture of any 1 alcohols with some butyl, and Lexy1 alcohols and esters.

39. Define Molasses?

Molasses is a dark coloured, viscous liquid left after the crystallization cane sugars from

cane juice.

40. What is the other name of power alcohol?

Ethyl alcohol

41. What is the composition of Molasses?

Molasses contains 35-40of cane sugar (or) sucrose

42. What is the molecular formula sucrose?

C12H22O11

43. In what substances sucrose soluble?

(i) Water

(ii) Methyl alcohol

(iii) Ethyl alcohol


33


34/106


44. Give the example for detergent

Sodium dodecyl benzene sulphate

PART B

1. Briefly explain the edible oil extraction methods?

Figure: Vegetable extraction methods

Seeds cleared, and hulled stream cooked at 220-250F for 15-20 min, then pureed either by

Continuous screw extruder (or) expeller Batch Hydraulic press


34


35/106


Alkali such as NaoH (or) Na2Co3(or) Na2CO3is added to remove free fatty acids as foots by

centrifugation. Bleaching is done with adsorbent clay as fullers earth and with adsorption carbon

Filtration is done on pre-coat rotary vacuum filter.

An alternate route to solvent extract by use of prop are

2. Explain the hydrogenation of vegetable oils:

Hydrogenation is the unit process which is need in the fat and oil industry to removedouble bonds, raise the melting point of the fat and remove its resistance to rancid oxidation. The

major end products in India is vansapathi

1* 31 3 3 5 2 1* 32 3 3( ) C 3 ( ) .N!xC H COOH H H C H COO C +

Nickel catalyst preparation

( ) ( )1+$

2 2 2 2bare22 2 2

o!lN! HCOO H O N! CO H H O + + +

Nickel catalyst preparation (Raney or spongy Ni catalyst method)

2A1.Ni+6NaoHNi* +2NAA1O3+ 3H2

Raney Nickel


35


36/106


Figure: Hydrogenation of vegetable oils

3. Explain the basic principles and reaction involved in soap manufacturing?

The grease is pulled away from the surface to be cleaned by the Keymechanism shown

The success of any cleansing agent is to supply components with hydrophobic any

hydrophilic groups which will also appreciably decrease surface tension and increase wet ability.

Sulfonated Fatty alcohols:

ROH + HOSO3CH ROSO3H +H2O


36


37/106


Fat Splitting

(RCOO)3C3H5+ 3H2O 2RCOOH+C3H5 (OH)3

Triglyceride Fatty acid

(b) Soponification reaction:

RCOOH + MOH R.COOM + H2O

Soap

4. Explain the process description for the production of soap-Raw materials:

Refined Tallow, recovered and defined grease, coconut and palm oils are the principal fatty

constituent metal oxides such as zno are frequently added as fat splitting catalysts. Alkali for

soponification and builder-type additives mainly rorm. Complete the raw materials

Caustic soda and vegetables oil are 2 raw materials for the production of toilet soaps as the

use of animal fallon is not allowed in India. Distilled fatty acids derived from vegetables oil such

as palm oil (or) other solvent extracted oil and miner oils are an important constitutents. Demand

supply gap for vegetable oils and its derivatives is met thro imparts.

Basis:

For 1 tan of anhydrous soap

Oil (or) fat 1.1 tons50% NaoH 0.3 ton

Sodium silicate 0.8 ton

Steam 1.5 tons

5. Flow diagram for the continuous production of fatty acids and soaps.


37


38/106


Figure: Continuous process for fatty acids, soap and glycerin

Glycerides plus catalyst are added at the bottom of the hydrolysis tower when high

pressure water at 230- 250C is passed. Reaction occurs witha 15-20% glycerin solution being removed from the bottom of the

tower.

The fatty acids passed overhead to a flash tank to remove excess steam

The crude fatty acids are vacuum distilled and the condensate in the distillate reeiver either

available as a marketable product (or) a soap manufacture.

6. Write the methods for the production of detergent manufacturing:

Molten sodium is added slowly to coconut oil in an aliphatic solvent plus etherification

alcohol. Such as any 1 alcohol. The reaction occurring are


38


39/106


2

# 11 11

2

1 2 1 2 2

2 2 2

#

( !nd!cates act!-e )

R

/ # R

H O

C H OH Na O H ONa H

R COOCH CH OOH

R COOCH CH OOCH

+ +

3 2 3 2

1 2

2 2

R 2

R

R

R COOCH CHl OOCH

CH OH

CH OH

3 2

3 5 3

R

( )

CH OH

C H OH +

After reaction is completed, the batch is pumped into a water tank where the mixture settles into

three layer; the top is the high molecular weight alcohol, the intermediate layer contains

regenerated reducing alcohol, and the bottoms have caustic soda and glycerin for recovery, the

economic of the process compared to pressure compared to hydrogenation equipment on one

hand and higher cost sodium reluctant and more complex product separation on the other.

6. Explain the manufacture of glycerin from propylene via Ally chloride. Give the reactions.

This process produces the intermediate Epichlorohydrin, a basic ingredient of epoxy region

manufacture.

7. Explain the reaction and process for the production of glycerin thro Actolein from propylene


39

H H H

HO

CH C C CI

Epichlorohydrin


40/106


8. Explain the process description for the production of glycerin thro fatty acids?

The dilute glycerin (sweet water 0- is put thro successive beds of onions and cation

exchange resings to remove some colour and dissolved salts. The liquid effluent is concentrated by

triple effect. Evaporation and vacuum distilled to produce industrial grade (99%) yellow glycerin.

A final purification step is performed using activated carbon to obtain water white U.S.P glycerin.

Methods of production:

Classification of process:

(i) Natural product triglyceride hydrolysis

(ii) Synthetic glycerin from propylene (petrol chemical processing)

Allyl chloride route

Acrolein route

The acrolein route produces acetone co-products

9. Explain the chemical composition and physical properties of edible oils.

(i) Fats and oils mixture of glycerides of fatty acids where R1, R2and R3are not necessarily the

same

R1COOCH2 R2COOCH

R3COOCH2

By terminology of the industry ,oil are all Liq. And fats are solids at normal temperature


40


41/106


Waxes: Mixed esters of polyhydric alcohols usually solid at room temperature.

Effect of degree of saturation:

Number of double bonds in the fatty acid radical controls the melting point and chemical

reactivity as shown in the following task.

Name Composition No. of double

bands

Melting Points Reactivity to O2

Stearic C17H35 0 69 Nil

Oleic C17H33 1 14 Fair

Linoleit C17H31 2 -5 Rapid

Linolenic C17H29 3 -11 Extremely rapid

The ability is react with O2enhanced the use of unsaturated fatty acids as film forming vehicles for

plants. It also is the cause of rancidity is edible fat products.

10. Give the brief introduction about edible oils and essential oils?

Edible oils are naturally occurring compounds based on long chain fatty acids and esters

(particularly glycerides esters) as well as derivations such as glycerin, long chain fatty alcohols,

sulfates and fulsonates, products form these compounds are used for food, sanitation, polymers

and in the paint industry.

In India where facts of animal origin such as fish oil lard are seldom used as cooking media,

that term vegetable oil is used as a synonym for edible oils. However it neds to be remembered

that there are on the one hand, vegetable oils such as castor oil and linseed oil which are non-

edible and on the other hand, edible oils like groundnut and coconut oil which are finding

increasing industrial applications as in cosmetics, soap making etc. Edible oils are a major source

of nutrition for the people in the country. Oil cakes, which are by-products of the oil extraction

process are important sources of animal nutrition. They can also be processed into protein rich

edible flour.

India has a highly developed oil based industry employing more than 15 million persons.

However, it remains an essentially food oil industry, accounting for as much as 83 percent of the

total supply of vegetable oil in the country. The major non-food users of oil are the soap and

varnish industries . these are the essential oils

Solvent extraction is a continuous chemical process for processing oil seeds such as


41


42/106


groundnut, soyabean and rapeseeds as opposed to physical crushing for oil extraction. Crude

vegetable oil, the main product from the solvent extraction process, is primarily used in the

manufacture of refined edible oils and vanaspathi, and to a lesser extent in glycerols and fattyacids use din soaps and other toiletries. While there are number of other value-added products

for varied application, the domestic industry and consequently the market for these products is

nascent.

11. Give an account on the classification of the cleansing compounds.

Soaps- compounds of the type R.COO.M where R.COO. is fatty acid radical representing

oleic, stearic, plasmatic Laurie and myristic. These are usually present in soaps as mixtures

based on glycerides raw materials M is the an alkali element such as Na or K. Detergents synthetic organic chemicals which promote better surface tension lowering

than soap Anionic (give R in water).

R,OH + HO.SO3HRO.SO3H + H2O

The sulfated compounds are quite stable in alkaline acid and hard water.

The molecular structure of R is important in determining a compound is biologically soft, straight

chain-normal structure gives a soft ABS.

Cationic:-

These have no strong detergent characteristics, but do have germicidal properties.

Non- Ionic:

Alkyl-aryl ethlylene oxide derivatives

Alphatic polyhydric alcohol esters.

Detergent builders:

Fluorescent dyes as brighteners.

Zealotries as alternative phosphorus free builders.


42


43/106


12. What are the major engineering problems faced in the hydrogenation of oils?

(1) Thermodynamics and Kinetics:

(a) Heat of reaction:

The heat of reaction for hydrogenation of oils is mildly exothermic the energy liberation

during hydrogenation requires a normal amount of water cooling via cooling coils.

(b) Temperature:

This variable is kept below 200C to avoid side reactions such as pyrolysis and to prevent

sintering of the porous catalyst.

(c) Kinetic rate factors:

For a gas-liquid reaction of the hydrogenation type

H2(g) + oil (I)fat (I)

Research has shown that a series of rate processes exist with 8 kinetic resistances.

The rate behaviour was characterized as,

Surface reaction and adsorption controls reaction rae in the vicnity of 100C.

2) H2handling problems:

Hydrogen gas has a wide explosive limit range. All equipment should be leak-tested with

Freon or helium detectors before operating, carbon steel can be used throughout for oil

hydrogenation to prevent hydrogen embitterment.

13. Write short notes on castor seed and soybean?

a) Castor seed:

India is one of the major producers of castor seed accounting for about 28 percent of the

world production the annual production of castor seed is around 5 lakh tones while that of castor

oil around 1.8 lakh tones. By acting in concert with the Technology mission on oilseeds, the


43


44/106


Gujarat and Andhra Pradesh Governments have helped growers increase production. Inedible

castor oil has two significant potentials.

With suitable processing castor can be used in the manufacture of soap to the extent of over

25 percent thus relieving to some extent the pressure on other edible oils, by being used in

conversion and in the lubricant industry castors oil has a good export potential especially in view

of the high price of the high price of petroleum products.

b) Soyabean:

Soyabean is not new for India. Black soyabean has been cultivated for ages in the low hills

of Kumaon and Garhwal region in India. (U.P) as well as on the foothills of the Himalayas and insome scattered pockets of central India. However, strangely enough, the crop has never been

popular in the India sub-continent and other tropical countries. The importance of soyabean in

Indian agriculture as a crop to narrow the oil and proteins gap has now been generally

appreciated, studies have indicated that the Soya flour, a by product can be used for fortification

of wht or other cereal flour up to 20 percent without detectable difference from the view point of

taste or appearance, but can considerable increased nutritional quality.

Besides, soya flour is known for its value as cattle feed in order to narrow the gap between

the availability and increasing requirement of nutritious feed for livestock.

14. Discuss about the raw materials and process description of hydrogenation of oils?

Raw materials:

Major raw materials are oils to be hardened and purified hydrogen which can be obtained

from several sources such as :

H2O or chlor- alkali

Steam iron reaction of steam on Fe followed by regeneration with water gas

Synthesis gas process:

Process description

Batch operation is used because of large residence times (1-3 hrs) and variation in oil input

and product properties from day to day. Batch hydro generators can treat 5-30 tons of oil per

batch, are equipped with coils for heating and cooling, and turbine agitators to disperse the


44


45/106


injected hydrogen.

A typical hydrogenation batch process operates as follows. Oil is charged to the reactor,heated and evacuated to drive off air and water. A catalyst oil slurry is pumped in, the catalyst

concentration is 5 to 15 kg per ton of oil Hydrogen is introduced and the steam is turned off since

reaction is mildly exothermic. After the derived hydrogenation has ensured as checked by an

iodine number iteration, the batch is cooled and filtered to recover the catalyst for reuse.

The hydrogenated oil is next deodorized in a Dow herm heated, steam, sparking vacuum

tower which operates on a continuous basis. The oil is next decolorized with fullers earth, carbon

or similar absorbent , then filtered, mixed with vitamins and sent to the packaging storage

operations. This involves refrigerated slow-cooling in packaged tins to reproduce the granularstructure of ghee.

15. Write short notes on Rice bran oil, Linseed and coconuts ?

Rice Bran Oil:

Rice bran is the most important source of edible oil among the unconventional sources. Rice

bran is the brown coating around the white starchy rice kernel which is obtained by dehisicing

paddy and polishing the rice. Despite the impressive grown of rice bran technology in thecountry, only a third of the available potential has been exploited. India produces about 80 million

tons of paddy annually.

Linseed:

Linseed is most commonly used for non-edible purpose. It is dual purpose crop yielding

oil and fiber. The relative contribution of this crop to the countrys total oil seed acreage and

production are 11.7 percent and 5.2 percent respectively. The crop is grown mainly as a source of

oil which is commonly used for cooking in M.P. and U.P, but a major portion is used in Industries,as in manufacture of plants and varnishes.

Innovative processes have been developed which can improve the quality and quantity of

yield from coconut. Not , India imports coconut oil in spite of being the third largest grower of

coconuts in the world. India has the potential to export 1.25 lakh tons of coconut powder, 1.2 lakh

tons of coconut oil and one lak tone of other products annually after metering domestic

requirements. This plant is to used wet processing techniques which use 93 percent of the

coconut.


45


46/106


UNIT-III

PART A

1. Butadiene is formed by the reaction of the raw materials of what?

(or)

Explain the formation of Butadiene?

(i) It can be obtained by steam creating of hydrocarbon gaser:

(ii) dehydrogenation of bur tone

(iii) Dehydrognation (or) dehydration of ethanol.

2. What are the catalyst involved in fixed bed catalytic cracking proceed?

(i) Sin2Al2O2- 6 mesh pellet

(ii) Bauxite (A12O3Sio2Fe2O3H2O)

3. Which catalyst is used in the manufacture of acetone by dehydrogenation of iropropanol?

Cu is used as catalyst

4. What are the other names of crude Petroleum?

1.Rock oil

2.Black oil

3.Mineral oil

5. What are the raw materials of the production of ethanol a miner?

Ammonia Ethylene Oxide


46


47/106


6. What is the chemical Composition of Bauxite:

(A12O3Sio2Fe2O3H2O)

7. Give and example of exothermic dehydrogenation?

Methyl cyclohexane Toluene

8. Give the example for Cyclization reaction

Ethyl chloro Pentane Methyl cyclohexane

9. Give the example for isomerization reach.


47


48/106


Ethyl cyclo pentane methyl cyclo Hexane

10. What are the user of ethylene?

It is use in the manufacture of

(i) Polyethylene

(ii) Styrene

(iii) Vinyl chloride

(iv) Ethylene dioxide

11. What is the use of iropropanol?

(i) In the manufacture of acetone

(ii) As solvents

(iii) In chemicals

(iv) In drugs

12. List the method of production of Butadiene?

(i) dehydrogenation of Butane

(ii) dehydrogenation of Butylene(iii) dehydrogenation dehydrogenation of ethanol

(iv) Steam cracking of hydrocarbons.

13. Write main reaction involved in the formation of butadiene by dehydrogenation of butane?

C4H10CH2= CH- CH = CH2+ 2H2; DH = 32.2 KC-eL

Side rxn : C4H16C4H8+ H2 H butylenes

14. What is the Chemical formula of Butadiene


48


49/106


CH2+CH CH = CH2

15. What are the different methods for the production of ethylene?

(i) Steam Pyroylin of petroleum from LPC and Naptha feed stocks.

(ii) Thermal Pyrolyin of ethane and /or propane

(iii) Dehydration of ethanol.

16. How we can remove carbon deposits during Cracking?

We can remove it by applying Stem

Air oxidation

17. Example of fir the hydro cracking reaction is

CH3(CH2) CH2+ H2C3H8+ C4H10 H= 9.74

Kd

18. What is the use of quenching operation?

It is applied to avoid back (or) side reaction is required where low contact timer high term

condition exit.

19. What is the use of octane number?

It shows the degree of amti-knocking property of gasoline.

20. How we can product phenol?

Phenol can be4 produced by the Catalytic oxidation of toluere

21. How we can produce pthalic anlyaride?

It is produced by catalytic Oxidatory of naphthalene


49


50/106


22. How Styrene is produced?

Styrene can be produced by Dehydrogenation of ethyl benzene.

23. What are the classification of Petroleum?

Paraffin base

Napthelene base

Intermediate base

24. What are the different methods of refining petroleum?

(i) Fractional distillation

(ii) Cracking

(iii) Treating

25. Define the term Cracking.

By virtue of this process , the high boiling range components can be disintegrated into

lower boiling range components with lower molecular substance.

26. What are the classification of cracking?

(i) Thermal cracking

(ii) Catalytic Cracking

27. What are the different types of catalytic cracking?

Fixed bed catalytic cracking Moving bed catalytic cracking

28. What are the Catalytic used in Fixed bed Catalytic Cracking?

(i) Sin2AI202 6 mesh pellet

(ii) Bauxite (A1203Sio2Fe2O3H2O)

29. What is meant by knocking?

In internal combustion engine, where gasoline is used as fuel operated as high load and low


50


51/106


speed, a Sort of rattling noise with constant pitch is developed from the combustion is known as

knocking.

30. Define Compression ration:

&he -olume at the end o0 suct!on stro%erat!on:

at the end o0 the com'ress!on stro%eCompress!on

Volume

31. Explain Octane number.

It is ration of the percentage of is o-octane is the mixture of is o-octane and n-heptane which

matches the fuel under.

32. Name some innibitors added to the gasoline.

(i) Butyl amino phenols

(ii) Benzyl amino Phenols

(iii) Phenylene diamines

33. Define cetane number.

It is defined as the ration on the percentage of cetane (or) hexadecane (C16H34) in the

mixture of cetane and methyl-nupthalene which matches the fuel under knocking characteristics.

34. What are the additives added to dieser?

(i) acetylene

(ii) acetone

(iii) diethyl ether

(iv) ethyl nitrate

35. What are the residues obtained from Petroleum?

(i) Greases

(ii) Petroleum

(iii)Asphalt

(iv) Road oils

(v) Petroleum coke

36. What are the uses of ethylene?


51


52/106


Ethylene can be used for the manufacture of

(i) Polyethylene

(ii)Styrene

(iii) Vinyl chloride

(iv) Ethylene dioxide

(v) Ethanol

(vi)Ethyl chloride

(vii) Ethylene dichloride

37. What are the different methods for the production of ethylene?

(i) Steam Pyrolysis of ethane/propane

(ii) Steam Pyrolysis of petroleum from LPG and Naptha feed stock.

(iii) Dehydration of ethanol

38. What are the user of isopropanol?

It can be used.

(i) In the manufacture of acetone

(ii) as solvents

(iii) in chemicals

(iv) in drugs

39. What are the different methods for the production of Butadiene?

(i) Dehydrogenation of butane

(ii) Dehydrogenation of butylenses

(iii) Dehydrogenation dehydration of ethanol and

(iv) Steam cracking of hydrocarbons.

40. What are the main Consistent of Rubber?

Surplur

Zine oxide


52


53/106


Stearic acid

Accelerator

41. What are the main Compositions of crude Petroleum?

(i) Paraffin (CnH2n+2)

(ii) Napthalene (CnH2n)

(iii) Aromtic hydrocarbons (Cnh2n-4)

42. What is meant by Flash point?

It is the minimum temperature at which an oil gives Sufficient amount of Vapour so as toform and explosive nature with air.

43. What are the different types of gasoline?

(i) Natural gasoline

(ii) Straight over gasoline

(iii) Reformed gasoline

(iv) Aviation gasoline

(v) Polymer gasoline

44. Define the term Viscosity breaking (or) Visbreaking

The viscous oils and residues obtained after thermal cracking are further subjected to

cracking in order to produce fuel oils is called Viscosity breakenin.

45. Define Smoke Point.

The maximum flame height in millimeter at which the fuel without smoking when

determine in a smoke point apparatus under the specified condition is called Smoke point

46. What is Sweetening?

The process of removal of Sulphur from petroleum is called Sweetening.


53


54/106


PART-B

1. Explain the Visbreaking Operation in Petroleum refining process.


54


55/106


It is the operation to recluce the Virlosity of the oil. In this figure , feed stock comprising

Variety of materials ranging from asphalts, short residerums to medium oils is blanded separately

and Parred thro heat exchanging system. (i) the temperature rise in such exchange is close to

250C. The Prcheated stock, is heated din the furnak (2) to attain a temp of 470C, a pressure of 10-

15 kg/cm2essential to keep the coke forming reactions in dormant stack. Obligingly steam

admission in to feed stock cheeks coke formations, thereupon the life of tubes can be Value (3).

Only to be quenched in a quencher (4) effectively with processed heavy oils. The light fractions

and bottom fractions from this quencher go into the distillation column(5) . At the top of the

column, the condenser system separates water and supplies adequate light fraction as reflux.

Column these light fraction will gases are sent to an extractor is meant to dissolve gasoline like

fractions in circulating oils and the bottom section of the extractor acts as the stripper to free the

gases. The circulating oil with dissolved fraction is again sent back to the distillation column and

sent to the stripper (6) The circulating oil is tapered as a bottom products.

2. Explain the operation of Neptha cracking.

Naptha cracking is appropriated to product olefins. Mainly ethylene and propylene. In

fact any petroleum stock is suitable and in the position to replace naptha, which is preferentially

reserved for steam reforming process.

C2H6C2H4+ H2 C3H8C2H4+ CH4 C3H6+ H2


55


56/106


C4H10C2H4+ C2H6 C3H8+ H2

C4H6+ 2H2

When ethanol and propone are chosen as feed stocks, the following points must be pondered.

Naptha cracking for olefins is Schematically present in figure. The Hydrocarbon feed stock

is Preheated and cracked in presence of stem in a fubutal furnace.

(i) The furnace is maintained at high temperature of 800-850C as soon as the furnaceefficient record a tem of 800-850C emerge out of fulnace, they are cooled in a transfer line the

exchanger.

(ii) Which is set apart for production of high pr. Steam (100 - 120Kg/cm2). Still

hot, the products are rapidly quenched by showering with feedback stock (or) with Circulating

oils. Direct quenching with H2O is also practiced in some cases quenching with oil is done in

pyloylis fractionation.

(iii) Where fraction also Carried Out simultaneously. The bottom pdts shall be heavy oils (or) fuel


56


57/106


oils; mostly polymer produce. The lighter fraction are cooled in a reflux, Condenser, at the top of

fractionators . In a reflux condenser, Separation of gaseous products from light distillates take

place. The gases are always infested with acid constitutents like Co2, CO , H2S, SO2. Oxides ofnitrogen etc and these are stripped off by suitable solvents. The acids free are new cooled and

them compressed to a pr of 30-40 other whereby Propane and high components are liquefied.

3. Explain the term Hydro cracking.

Charge stock recycle hydrogen and make up hydrogen and mixed and passed thros a

heater. The mix entus the reactor (1) frame the top while cold hydrogen is admitted to the reactor

(i) from the top while cold H2is admitted into reactor at diff parts. The efficient flam the reactor

are immediately heat exchanged with the c/s chilled and fed into a high px separator (2), whereH2 is separated. This h2 is contaminated with h2s and nh3, have a proper treatment for the

removal of these contaminated with H2S is required and is Practised in the heater. (5) The

recovered hydrofn is compressed to the required pr. And recycled back. Treated stock from high

px relcaler goes to a low px separator (3) where fuel gas (up to C3fractions0 H2S are obtained his

fractions from the bottom of their separated. The heavy oil from the fractionator is recycled back

to the reactor.

Figure: Hydrocracking


57


58/106


4. Explain the team of Reforming process and draw the neat flow diagram.

Catalyze reforming is used to convert hydrocarbons to aromatizes which have octanerabing.

Figure: High pressure platinum catalyst reforming process


Naptha fed stock is protracted by mild hydrogenation high temp bauxite reaction, (or)

absorption to remove sulfur, nitrogen and metals which lower pt catalyst activity. The treated feed

is mixed with recycled H2prcheated and charge to three (or)more cylindrical reactor in series.

Reheat interchanges are required since in the overall reaction is ender thermion.

Fixed bed catalyst units are used because handling of expensive pt catalyst in a fluidized

bed would create too high an operating loss via dusting. The catalyst can be regenerated every 2-3

months by burning off the Carbonaceous deposit with mixtures of steam air carbonaceous deposit

with mixtures of steam, all and flue gas. Non-lubricated compressors are used to recycle H2, thus

avoiding coking of catalyst by lubricating oil


58


59/106


4. Explain the isomerization Process.

Catalystic isomerization of n-paraffins to isomers for alkylation feed stock is necessary

refinery operation since n-paraffins are of little value as an end-products.

Feedback, mainly from virgin and coking distillate, is dried and preheated, fed to a reactor

is designed for efficient vapour- solid, vapour- liq liq-liq (or) liq- solid contact, depending on the

reactant and catalyst from respectively. HCl and make up Alcld3 are also added Alcid3 recovery

by distillation (or) condensation is necessary because it is volatile at reactor conditions and slightly

soluble in water. Removal of light ends by flashing followed by HCl stripping caustic wash, and

fractionation are standard operations.

Figure: Low temperature isomerization process

5.List the processing methods for the production of methanol an craw the flow diagram?

H2and CO in a mole ratio of 2.25 is compressed to 3,000 5,000 PS mixed with recycled gar,

and fed to a high pr. Converter Internal preheat is usually employed. The reactor is copper-linedsteel and contains a mixed catalyst of 2n or Mg (or) a1 Oxide. The temp is maintained at 300-


59


60/106


375C by proper space velocity and ht exchanger design.

The exit gases are cooked by exchange with reactants then with water the method cendersesunder full open or pr to maximize yields CN 50%. Conversion pel passi. The liq methanol is

deprecrized, purified by permanganate to remove trace of ketoner, aldehydes, and other such

impurities.

Figure: Methanol via synthesis gas route

6.Explain the production of formaldehyde from methanol.

Non purified air, compressed to about 0.2 atm gauge IN preheated by exchange with reacting

gaser and then conveyed to a methanol evaporator. Conditional are set to keep the CH3 OH: O2

ratios in the 30-50% range. The mixed gasser is preheated, sent to a reactor where liver (or) copper

gauze (otr) their oxides are catalysts. Catalysts activity is controlled to maintain a balance between

the endothermic dehydrogenation and exothermic oxidation rxn a reaction conditions of 450-

600C. Some complete Combustion takes place.


60


61/106


Figure: Formaldehyde from methanol

The product gases are absorbed in a water scrubber which is cooled by external circulation,

and the fractionated to recover approximately 15% unreacted methanol for recycle . Ultimate

yields of 85-90% wt % bated on methanol are typical.

Reactions:

2 2 2

2 2

2 2 2 2

1, = 3* %cel

2

"rols!n:

C = 1+. %cel

!de rn:

3C 2 =1#2%cel

2

CH OH O HCHO H O

OH HCHO H

OH O H O CO

+ + +

+

+ +

C


61


62/106


8. Explain the reaction involved in the production of Perchloro ethylene and draw neat diagram

Chemical reaction:

Pyrolysis of CCl4:

2CCl4Cl3C.CCl3+ Cl2

Hexa calloro ethane

Propane chlorination to yield Cel4co-products:

Cl3C.CC3Cl2C = CCl2+ 2Cl2

Chrorination of trichloroethylene to peta chlorine ethylene

2CCl4Cl2C = CCl2+ 2Cl2


CCl4is vapourized, passed into resistively heated carbon electrode furnace at 800-900 c and

pyrolyzed to pelchlozo ethylene, hexa chloro ethylene, and chlorine. The effluent goes to a partial

condenser , held at 80-85C where CL2 Plus unreacted CCl4are separated from heavy ends. The

CCl4is stripped of Cl2in a condenser and recycled. The heavy ends are distilled to separate

pechloroethlene from hexa chlora ethana. The lather can be recycled from further Pyrolysis or

further purified via distillation.


62


63/106


Figure: Perchloroethylene by pyrolysis of carbon tetrachloride


63


64/106


9. Steam cracking of hydrocarbons for the production of ethylene and acetylene.

Figure: Ethylene and acetylene production by steam cracking of hydrocarbons0.

Chemical rxn:

C2H2n + 2H2O + O2(optinal)C2H4( 4 15% ) +

C2H6+ C2H2+ H2+ C0+ CO2+ CH4+ CH4+ C2H6 C3H8+ C4H10+ C4H6C

The process to be detailed here is high temp thermal reforming using ethane, propane,

butane, and (or) tig naptha superheated stem is mixed with the hydrocarbon is fed thro the heated

coil of a pyrolyris furnace the c2 c4 feed is pyrolysized is a separate furnace be cause diff residence

time-temp conditions are required. The pyrolysized gases are quenched in a wasted heat steamboiler and ten scrubbed with as oil to remove solids and heavy hydrocarbons before sending to


64


65/106


66/106


11. Explain the production of ethylene dichloride

Figure: Ethylene dichloride production

Chemical reaction

CH2= CH2CL2 CLCH2CH2CL

Ethylene (with or) without C2H6, CH4and H2diluent) is mixed with chlorine and bubbled

thro a liq phase reactor. Ethylene dichloride product serves as the reacting medium. Heat of

reaction is controlled by external heat exchange and recycle, (or) by coil (or) jacked heat transfer to

hold the reactor at 45-50C with a pr of 1.52 atms traces of ferric chloride or ethylene dibromide as

catalyst give 90-95% yield with little dimmer formation. Gaseous products are cooled in 2 stages

to strip the acid gas of ethylene dichloride. The liquid product is allcali washed and fractionated.


66


67/106


12. Explain the formation of vinyl chloride thro ethylene dichloride pyrolysis.

Chemical reaction

CH2CL . CH2CL 25$$

4 atm

CCH CHCL HCL= +

Ethylene dichloride (EDC) vapour at 4 atm is dried by silica gel and sent to a stainless steel the

baler cracking furnace. This is externally flue gases fired and controlled at 480 520c. The contact

surfact catalyst with in the tubes is pumice (or) charcoal. The conversion per part is around 50%

and the ultimate yield is 95% -96% spray quenching with cold EDC prevents back-reactionuncondensed gases are sent to a surface heat exchanger to remove the balance of the EDC and

vinyl chloride.

The non-condensibles containing HCL are either sent to the acetylene HCL process.

The condensate is fractionated with the EDC bottoms returned for recycled and vinyl chcoride

monomer taken from over head.


67


68/106


Figure: Vinyl chloride via ethylene dichloride phyrolysis

13. Explain the manufacture of vinyl chloride thro acetylene HCL reaction

CHEMICAL REACTION

2

1#$ 2$$

1 atmCH CH HCL CH CHC"

= = =

Figure: Vinyl chloride via acetylene HCI reaction

Acetylene and dry HCL in 5-10 % molar excess are vapour blended by jet mixing in a pipe and


68


69/106


passed thro a tubular catalytic reactor containing carbon pellets impregnated with Hgl2the tem is

maintained at 160C and is gradually raised to 215c as the catalyst deteriorater. The effluents

gaser contain vinyl chloride which is separated from unreacted acetylene plus hydrogen chcoride,these unreacted materials being recycled.

14. Ethylene oxide thro air oxidation of ethylene

Chemical rxn:

2 2 2 2 2 2 2

1( )

2 25$ 3$$

45 atms

=2+.2 %cal

AgoCH CH O CH CH CO H O

C= + + +

Ethylene of 95-98% purity an air are compressed separately, mixed together giving 3-10 C2C4and

volume concentration and passed over a catalyst of ago on a porous inert carriers such as

Alumina. A side rxn suppressing agent such as ethylene dichlorider is added to the feed to reducethe competitive oxidation reaction to CO2+ H2O

The rxn is highly exothermic and is best carried out in a fixed bed tabular reactor in which

heat transfer salt (or) . Dow them is pumped around the tube within the shell to maintain a 250-

300c temp Heat is received is a Walter steam boiler.

The effluents gases from the reactor are water washed under pr the absorbed ethylene oxide

is sent to a packet bed absorber fractionator are taken overhead.


69


70/106


Figure: Ethylene oxide by air oxidation of ethylene

15. Describe the preparation of Acetone by dehydrogenation of isopropanol

Catalytic dehydrogenation of isopropanol

( )

( ) ( )

3 3 3 22

3 2 3 3 22

1

2

CH CHOH CH COCH H

CH CHOH O a!r CH COCH H O

+

+ +

Isopropanol vapour Compounded to 3 atms. Is permuted by reactor effluent heat exchange

and passed thro a tubular catalytic reaction maintained at 500IC with the catalyst containing ofCu or Bros deposited on porous carrier. The hot rxn gases pall thro a water condenser and them

into a water scrubber where final traces of isopropanol and acetone are removed from H2 to gie

product grade acetone over head and dilute isoproponal bottoms. These are further recycled to

give 88% isopropanol.


70


71/106


Figure: Acetone by dehydrogenation of isopropanol

UNIT IV

PART A I

1. Define Polymer?

Polymers are composed to molecules of molecular weight from about 103to 107. Polymer is

made up of repeated basic units produced form monomers.

2. Give example for Thermoplastic and Thermosetting?

Cellulose derivations thermoplastic

Phenol formaldehyde Thermosetting

3. Give the structure of polyethylene?


71


72/106


H C = C H

H H

4. Distinguish thermoplastic and thermosetting?

Linear or slightly branched molecules

Solvent soluble

Cane be repeatedly melted

Thermosetting:

Heavily branched

Solvent insoluble

Cannot be melted after forming

5. Give example for monomer and corresponding polymer?

Monomer Polymer

Ethylene PolyethylenePropylene Polypropylene

Butylenes Polybutylene

6. Differentiate addition and condensation polymerization?

Additional Polymerization:

These reactions are carried out under controlled heat and catalyst conditions. It is classified

as homogeneous and heterogeneous polymerization.

Condensation Polymerization:

It can be processed without or with solvent addition. It follows procedures used for low

molecular weight functional group reactants. It can be mixed in batch reaction vessel with catalyst

addition and heat control to avoid premature gestation.


72


73/106


7. What is emulsion polymerization?

Monomer and water emulsified with suitable reagent to yield spherical monomer particlesin the 1-10range called micelles. Over come the difficulties of heat control.

8. What are the uses of thermoplastics?

Useful for melt casting and spinning, injection molding and extrusion

9. What are the properties of plastics?

Most of the plastics have low scratch resistance Luster, clarity, reflectivity and permanentallowing.

10. What is fibre?

Fibre are thread formed solids with high tensile strength.

11. Give example for polyester and epoxy resin?

Decrease fibre nylon film polyesterEbichloroshychin epoxy resin

12. What is plasticizer?

Plasticizer one organic compounds addict to plastics to improve workability during

fabrication.

13. What is PVC?

Polyvinyl chloride

14. What are used of epoxy resin?

In film formation and adhesives.

15. What are polyester?

It is formed by condensation of poly functional acids or esters.


73


74/106


16. What are the classifications of polymer?

Thermo plastic Thermosetting

Elastomers

Fibers

17. What are the Elastomers?

Resistant solids with high flexural stronger

18. What are LDPE and HOPE?

Low density and high density polyethylene

19. What is meant by high polymer?

The high polymers are substances of vary high molecule weight, which may occur is nature

or chemically synthesized.

20. Define degree of polymerization?

The degree of polymerization is defined as the number of repeating unit is chain formed isa polymer.

21. Name some natural and synthetic polymers?

Polyethlene

Phenol formaldehyde

Polystyrene

Polyamides

22. What is meant by linear high polymer?

It is the repetition of the repeating units in a high polymer molecule is similar to that of the

links in a chains, it is called linear high polymer.

23. What is meant by homo chain polymer?

When the chain is made up of same species of atoms the polymer is known as hormochain

polymer.


74


75/106


24. What is meant by hetrochain polymer?

When the chain is made up different species of atoms the polymer is known as hetrochainpolymer.

25. Explain Regular copolymer?

When monomer units in a copolymer molecules are arranged in the chain in a regular

manner, the molecule is called regular copolymer.

26. What is meant by statistical copolymer?

When monomer units are arranged in an irregular manner the copolymer molecule is called

statistical or irregular copolymer.

27. What is meant by block copolymer?

Linear copolymers in which the like monometric units in relatively long sequences are

called block co-polymer.

28. Name some examples for network polymer.

Urea formaldehyde and phenol formaldehyde resins are some examples for network

polymer.

29. For what reasons plastics are used in wide range?

Plastics are used in wide because of their,

i. Toughness

ii. Water resistanceiii. Excellent resistance of corrosion.

iv. Easier for fabrication

v. Remarkable colour range.

30. Explain Thermosetting.

If heating takes blue in the final stages of the manufacture, the resin are said to be thermo

setting.

31. What is meant by thermoplastic polymer?


75


76/106


Those polymer which often on heating and regain their original properties polymer.

32. Name some common reinforcing fibers.

i. Cellulose fibers

ii. Fiber glass

iii. Carbon fibers

iv. Aramid fibers

v. Metal filaments.

33. Define Cellulose?

Cellulose is a structural material of the plant world is itself a polymer composed of 50 t 100

units of disacchanide cellulose.

34. Define the term blastmer used for rubber like polymer?

The terms blastmer is used for rubber like polymer which gains original shape when the

deforming stem is released.

35. What are the uses of adding filters and reinforcements to plastics?

(ii) increase thermal conductivity

(iii) Reset to heat distortion

(iv) Lower thermal expansion

36. What are the some general polymerization process?

Bulk polymerization Solution polymerization Suspension polymerization Emulsion polymerization

37. Define Polyester resins.

Polyester resins are complex esters formed when a dysfunctional alcohol is reacted with a

dibasic acid or anhydride.

38. What are the different methods of moulding of plastics?


76


77/106


I. Compression moulding

II. Injection mouldingIII. Transfer moulding

IV. Extension moulding

39. What are the uses of Bakelite

oElectrical insulating materials

oCycle parts

oAutomobile parts

oRadio and T.V. set bodies.

40. Define degree of polymerization:

The degree of polymerization may be defined as the number of repeating in a units chain

formed in a polymer, polymer are compared of molecules their mol wt very 103to 107.

41. Name some common reinforcing fibres:

Cellulose fibres Fiber glass

Aramid glass Metal filaments

42. Explain the property of thermo setting plastics?

They are usually harden stronger and more brittle than thermoplastic resins and they cant

be reclaimed back.

43. What are the common resins used in efficiently?

Actual, Fluoroplastics, nyklon, polypheylene oxidepolycarbonate etc.

44. What is other name of isopropyl benzene?

Cumene


77


78/106


PART-B

1. Explain the polymerization of Vingl polymer.


78


79/106


Figure: Polymerization process for vinyl polymer

Process:

In emulsion polymerization, a typical formulation is too path of H2O, 100 paths of Vingl

monometers, 1 p

chemical process inustries

Documents